1. Field Of The Invention
The invention relates to low plate out fluorescent pigment concentrates t methods of preparing such fluorescent pigment concentrates, and to the methods of formuaating such fluorescent pigment concentrates with polyolefins.
2. Background Art
Richter, J., "Fluorescent Dyes And Pigments", Focus Section, Europlastics Monthly, (Oct. 1973), is a general description of fluorescent dyes and pigments. Combinations of fluorescent dyes with white pigments, such as, titanium dioxide, are disclosed. Fluorescent dyes tend to cause cracking in polyethylene.
U.S. Pat. No. 3,796,668 discloses organic fluorescent dye colored PVC and its copolymers by way of enhanced initial fluorescent appearance of the product and by way of improvements in the resistance of the dye to fading upon exposure to light such as sunlight. These improvements can be achieved by combining as by blending a sufficient amount of chlorinated polyethylene with the PVC or its copolymers. If desired, additional improvement in fluorescent appearance and fade resistance can be achieved if certain vinyl resin stabilizers are added to the formulation. The addition of a non-mercaptide organotin or a barium-cadmium-zinc or a strontium-zinc stabilizer, the latter two categories of stabilizer preferably being used in combination with a chelator, will provide superior results than can be obtained with other types of vinyl resin stabilizer.
U.S. Pat. No. 3,922,232 discloses a fluorescent colorant comprising particles of a resinous precondensate colored with a fluorescent dye-stuff. The precondensate is a nontacky solid soluble in acetone and dimethylformamide at 25.degree. C., having a softening point of at least about 70.degree. C. and being derived from about 0.5 to about 2.0 moles of at least one aliphatic, aromatic or alicyclic polyfunctional acid components selected from the group consisting of carboxylic acids, esters and anhydrides, and one mole of at least one polyhydroxy compound selected from the group consisting of aliphatic polyhydroxy compounds and tris-(hydroxyalkyl) isocyanurates. At least one of the polyfunctional acid component or polyhydroxy compound has a functionality greater than 2. Additives such as titanium dioxide, low molecular weight polyethylene and ethylene copolymers (for example, ethylene-acrylic acid copolymers), and colloidal silica can be added to the precondenate or to the final colorant. The fluorescent colorants can be used for coloring polyethylene.
U.S. Pat. No. 4,172,063 discloses an abrasive resistant, reflective exterior marking composition useful for application to a substrate, such as, a cementitious substrate. The composition includes a vehicle component including an organic thermoplastic, resinous, film-forming material in an amount sufficient to form a tenacious bond with the substrate, a high visibility, flourescent pigment in an amount sufficient to produce flourescence, a sufficient quantity of an extender for the vehicle so as to render the composition readily applicable to the substrate by brushing or spraying or troweling, and the remainder being an inorganic aggregate material including a sand component, hydraulic cement in a cementitious amount and a glass fiber strand component. The hydraulic cement is Portland cement in the amount of about 0.1 to 500 parts by weight. The sand component is sand in the amount of about 0.1 to 500 parts by weight. The fluorescent pigment is present in at least about 0.10 parts by weight. The film-forming material is present in an amount of about 0.01 to 300.0 parts by weight. The glass fiber strand component is present in an amount of about 0.1 to 50.0 parts by weight. The extender includes a water-reducing agent in the amount of about 0.03 to 10.0 parts by weight and water in the amount of about 0.04 to 200.0 parts by weight.
U.S. Pat. No. 4,466,900 discloses a process for the preparation of a concentrated, storage-stable liquid formulation, which contains an anionic fluorescent brightener. The process includes treating a crude aqueous solution or dispersion of an anionic fluorescent brightener containing a sulfo group, with a semipermeable membrane which contains ionic groups and has a pore diameter of 1 to 500 A, so as to remove salts and synthesis by-products having molecular weights less than 500 and to remove part of the water. The concentrated preparation can be treated with formulation assistants, e.g., surfactants, and further additives, e.g., dyeing assistants. The liquid formulations can be used for the fluorescent brightening of natural and synthetic fiber material.
U.S. Pat. No. 4,657,697 discloses a method for the preparation of a fluorescent ink layer for a fluorescent thermal transfer sheet. The method includes first forming a solution of a mixture comprising at least one acidic monomer, at least one basic monomer and at least one fluorescent dye. An emulsion of the solution is formed and the emulsion is polymerized.
U.S. Pat. No. 4,442,017 discloses a composition which is a solid uniform blend and which includes one or more additives for organic polymers. Each additive independently is normally solid at room temperature and is an anti-oxidant, stabilizer, lubricant, flameproofing agent, slip agent, anti-blocking gent or anti-static agent. The composition also includes a compound which gives a detectable response to irradiation in the presence of the additives. The additives and the irradiation-responsive compound are in intimate cohesive contact with one another. The irradiation-response compound can be a fluorescent compound.
U.S. Pat. No. 3,230,178 discloses a bright pastel composition composed of a white pigment having n index of refraction of at least about 1.8 to 2.0, a daylight fluorescent pigment in an amount sufficient to impart a pastel coloration to the white pigment, but insufficient to render the composition daylight fluorescent, and a binder for the pigments. The pigment can be titanium dioxide.
SiLCRON G-100 is an aerosol-type synthetic particle silica without any surface treatment which is known to be useful in polyethylene coatings as a flatting agent, for example, to be useful in plastics for reducing plate-out and preventing blooming, and to be useful in plastics as an aid to the dispersing of other pigments and PVC film. "SiLCRON Fine Particle Silica, SiLCRON G-100", SCM Corp., Baltimore, Md.
U.S. Pat. No. 3,930,063 discloses a method wherein a large particle sized silica sol and a fluorescent dye are mixed together and applied as a coating to a substrate with the application monitored during coating by a light which renders the fluorescent dye visible. If the coating is blotched or uneven, corrections can be made during the run to provide a uniform coating.
U.S. Pat. No. 4,176,205 discloses a fingerprint powder for developing latent fingerprints therewith. Such power is composed of a powder carrier, especially a mixture of silica and talc, containing a coloring agent, preferably a fluorescent dye. The silica for example is Cab-O-SIL M5, which is a fumed silica.
U.S. Pat. No. 3,960,755 discloses a composition useful for marking and identification purposes. The composition includes a non-fluorescent solvent, a fluorescent material and a water-insoluble, tacky, amorphous, resinous material.
U.S. Pat. No. 3,666,675 discloses a method of producing luminescence using certain complex luminescent materials.
U.S. Pat. No. 3,970,660 discloses a chemiluminescent system comprising (1) derivatives of a polycarbonyl compound substituted with at least one nitrogen-containing hetero group and which may have an alkanol or amine substituent, (2) a hydroperoxide compound, (3) a diluent, and (4) a fluorescent.